The present invention relates to a gas convection oven comprising a heat exchanger for heating forced air in the convection oven in a manner which allows a uniform temperature distribution within the cooking portion of the oven.
Known gas convection ovens include a dividing wall defining a cooking portion of the oven, a blower disposed against the dividing wall and driven by an electric motor, and a heat exchanger over which air forced from the blower passes. The heat exchanger generally comprises a plurality of vertically extending rectilinear pipes disposed close to the blower. A gas burner is disposed below and is separated from the cooking portion of the oven and generates hot combustion gases which rise through the pipes of the heat exchanger. A flue is defined in the oven above and is connected to the pipes of the heat exchanger so as to exhaust the combustion gases to the outside of the oven.
Another gas convection oven is known in which the tubes of the heat exchanger have a semi-circular shape and laterally surround the blower.
However, these conventional gas convection ovens have the following disadvantages.
First, because the tubes of the heat exchangers are disposed at different distances from the circumferences of the blowers, it is not possible to obtain a flow of hot air in each prior art oven that has a uniform speed and temperature, and thus, a flow of hot air having a uniform temperature distribution cannot be uniformly distributed about the cooking portion of the oven. Accordingly, a satisfactory cooking of food supported at various levels in the cooking portion of the oven cannot be carried out.
Furthermore, another factor which contributes to the uneven cooking of foods in these conventional ovens is that there is an uneven distribution of thermal energy radiating along the vertically extending tubes of the heat exchanger since the heated combustion gases progressively cool as the same pass upwardly through the tubes in the oven.
Finally, because of the presence of the fume discharge flue defined at the top of the cooking portion of the oven and the combustion chamber extending from an area defined below the cooking portion of the oven, the ovens cannot be adapted for use in series with each other.